(a) Field of the Invention
The present invention relates to a display device and a manufacturing method thereof, and more particularly, to a display device and its manufacturing method that can minimize inflow of oxygen and moisture from the outside.
(b) Description of Related Art
Among flat panel displays, an organic light emitting diode (“OLED”) has some advantages because it is driven with a low voltage, is thin and light, has a wide viewing angle, has a relatively short response time, etc. The OLED includes a thin film transistor (“TFT”) having a gate electrode, a source electrode and a drain electrode. The OLED also includes a pixel electrode connected to the TFT, a partition wall dividing the pixel electrodes from each other, an organic emission layer formed on the pixel electrode between the partition walls, and a common electrode formed on the organic emission layer.
Here, the organic emission layer is susceptible to moisture and oxygen. Therefore, the performance and the lifespan of the organic emission layer are likely to be decreased by moisture and oxygen. To prevent the organic emission layer from deteriorating, an encapsulating process is performed to make an insulating substrate having an organic emission layer face combined with a cover substrate for blocking moisture and oxygen. Further, an organic sealant is formed along an edge between the two substrates, thereby joining the two substrates together.
However, the organic sealant has a relatively high permeability to moisture (i.e., about 10 g/m2 day), and the permeated moisture is likely to deteriorate the organic emission layer, thereby decreasing the lifespan and the performance of the flat panel display.